Circle a has area 500 in? . the diameter of circle b is three times the diameter of circle a.
estimate the area of circle b.

3382-299=3383- ? fill in the blank?

Bring the fraction a/a-4 to a denominator of 16-a^2

How many 3-digit numbers can you write using only digits 1 and 7? (of course, digits can repeat.) how many 3-digit numbers can you write using only digits 1 and 7? (of course, digits can repeat.)